A month ago, Ravens defensive coordinator Don “Wink” Martindale compared the NFL season to a marathon. He was about the millionth person in recorded sports history to do so. But few marathoners look like Brandon Williams, and that was his point.

“We’re trying to go for the whole haul here,” he said, well aware that gravity is unkind to 336-pound defensive tackles covering great distances. But unlike the 26.2-mile marathon in, say, Saturday’s Baltimore Running Festival, NFL games accommodate substitutions. There is no shame in stop-and-go football.

Entering Sunday’s showdown against the New Orleans Saints (4-1), an interior line rotation operating like a relay team has energized the Ravens’ race to the top of nearly every NFL defensive leaderboard. Center Matt Skura, a veteran of offseason battles in the trenches, called Williams, Willie Henry, Michael Pierce and Chris Wormley “definitely one of the best, if not the best,” groups of defensive tackles in the NFL.

It is hard enough to go play for play against one of them, Skura explained. But when one heavyweight exits and another enters, it can feel like an unfair fight.

“If we can get our guys off the field and get them rested, it’s big,” coach John Harbaugh said Friday. “Having a little more depth in the D-line helps, too. Those guys don’t need to be taking 60 snaps a game, for sure. You try to cut that in half if you can. They play better.”

The Ravens (4-2) lead the NFL in plays per game (75.8), a function of a possession-hoarding, third-down-proficient offense. But on defense, they’re allowing the ninth-fewest opponent plays per game (61.2). In Sunday’s 21-0 win over the Tennessee Titans, the Ravens had 76 snaps on offense; on defense, just 44.

Pierce joked Thursday that he and Williams “played, like, 16 apiece,” an incredible-sounding stat that actually undersold their participation in the shutout: 16 snaps for Williams, yes, but only 14 for Pierce. Not that he was complaining. With Williams sidelined early last season by a foot injury, Pierce twice played 60-plus snaps in 2017.

This season, none of the Ravens' interior foursome have played more than Williams' 45 snaps in their Week 2 loss to the Cincinnati Bengals. Henry, who missed the Ravens' first four games while recovering from hernia surgery, is averaging 31 snaps per game. Williams and Wormley have played 30.7 and 27.8, respectively, in their six games. For Pierce, it's 21.3 over four games.

CAPTION

Ravens offensive coordinator Greg Roman talks about starting the new offense from scratch and using new terminology and new schemes. (Kevin Richardson / Baltimore Sun video)

Ravens offensive coordinator Greg Roman talks about starting the new offense from scratch and using new terminology and new schemes. (Kevin Richardson / Baltimore Sun video)

“Yeah, that'll take a toll on your body by Week 12,” Pierce said, referring to his heavy workload in 2017. “You're burnt out, but you've still got four games to play and possibly the playoffs. It's doing wonders, man.”

“It definitely makes a difference,” Skura said. “You have, like, a 10-, 15-play drive, and you think you're wearing out the D-line, and they roll in a whole new group, and they're fresh, they're ready to go. So it definitely makes it tough because, as an O-lineman, you're like: ‘Man, I'm kind of worn down right now.’ ”

The Ravens haven’t allowed a second-half touchdown this season, a phenomenon that defies easy explanation. But when the streak does end, perhaps as soon as Sunday against the Saints’ top-scoring attack, the interior rotation is unlikely to be the culprit.

Well-rested linemen have a quicker first step, Skura said. They’re stronger. Sprints to the ball-carrier aren’t a chore but an instinct. Pierce said he has had “juice” in the fourth quarter this season; his legs feel less like Jell-O and more like a powerful engine, one that’s propelled him to No. 6 this season on Pro Football Focus’ defensive lineman rankings.

Though only Wormley finished with a sack Sunday, it was probably no coincidence that the Ravens finished with a franchise-record 11 the first time this season all four interior linemen were healthy. Harbaugh said afterward that, against a Titans offensive line that had allowed nine sacks all season, “You just felt the pocket collapse.”

“We’re getting to be where we’re full strength,” Martindale said Thursday. “That’s exciting. We’ve gone to the three H’s now: humble, hungry and healthy.”

Strength in numbers

While the Cincinnati Bengals' Geno Atkins, Pittsburgh Steelers' Cameron Heyward and Cleveland Browns' Larry Ogunjobi log significant playing time as the interior anchors of their respective defensive lines, the Ravens have taken a more balanced approach. Compare their share of their defense's week-by-week snap totals below.

Player; Week 1; Week 2; Week 3; Week 4; Week 5; Week 6

Michael Pierce; 40.6; 38.2; Out; 25.8; Out; 31.8

Chris Wormley; 57.8; 47.4; 51.5; 43.5; 22.5; 31.8

Willie Henry; Out; Out; Out; Out; 48.8; 52.3

Brandon Williams; 40.6; 59.2; 54.4; 35.5; 47.5; 36.4

Geno Atkins; 68.3; 75.3; 70.1; 71.4; 64.1; 74.0

Cameron Heyward; 85.4; 86.2; 74.0; 73.7; 70.8; 80.3

Larry Ogunjobi; 94; 87.9; 95.2; 85.9; 87.4; 80.0

Mike Preston breaks down three key battles that could help decide who wins the Ravens-Saints game at M&T Bank Stadium on Sunday.